How To Fix MPN01036 - The manufacturer part number is not unique

SAP Error Message - Details

• Message type: E = Error

• Message class: MPN01 - MPN Message: Material Master / customizing

• Message number: 036

• Message text: The manufacturer part number is not unique

What causes this issue?

Other material master records in the system use the same manufacturer
part number (MPN). Therefore, the MPN is not unique. If you have set
the output length of the material number to a value that is not long
enough to use the combined MPN and External Vendor, you can no longer
enter the material number.

System Response

Either the internal material number will be output, or you will have to
enter the internal material number in all material fields.

How to fix this error?

Change your material master records, so that the MPN is unique, or
shorten the MPN.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message MPN01036 - The manufacturer part number is not unique ?

  The SAP error message MPN01036, which states "The manufacturer part number is not unique," typically occurs when there is an attempt to create or update a material master record with a manufacturer part number (MPN) that already exists in the system. This error is part of the Material Management (MM) module in SAP and is related to the management of materials and their associated data.
  Cause:
  
  Duplicate MPN: The most common cause of this error is that the manufacturer part number you are trying to enter already exists in the system for another material or vendor.
  Incorrect Data Entry: There may be a typographical error or formatting issue in the MPN being entered.
  Configuration Settings: The system may be configured to enforce uniqueness for manufacturer part numbers across certain criteria (e.g., across specific plants or vendors).
  
  Solution:
  
  
  Check Existing MPNs: Before creating or updating a material, check the existing manufacturer part numbers in the system to ensure that the one you are trying to use is not already in use. You can do this by using transaction codes like MM03 (Display Material) or by querying the relevant tables (e.g., MARA, MARC).
  
  
  Use a Unique MPN: If the MPN is already in use, you will need to use a different, unique manufacturer part number for your material.
  
  
  Review Data Entry: Double-check the MPN for any typographical errors or formatting issues. Ensure that it matches the expected format and is entered correctly.
  
  
  Consult Configuration: If you believe the MPN should be unique but are encountering issues, consult with your SAP configuration team to review the settings related to manufacturer part numbers. They may need to adjust the uniqueness constraints if appropriate.
  
  
  Vendor-Specific MPNs: If the MPN is vendor-specific, ensure that you are associating the MPN with the correct vendor in the material master record.
  
  
  Related Information:
  
  Transaction Codes: Familiarize yourself with relevant transaction codes such as MM01 (Create Material), MM02 (Change Material), and MM03 (Display Material) to manage material master data.
  Tables: Understand the relevant tables in SAP that store material and manufacturer part number information, such as MARA (General Material Data), MARC (Plant Data for Material), and MAST (Material to BOM Link).
  Documentation: Refer to SAP documentation or help resources for more detailed information on managing manufacturer part numbers and material master records.
  
  By following these steps, you should be able to resolve the MPN01036 error and successfully manage your material master data in SAP.